Pilfer and tamper resistant strapping of sheet material including currency notes

ABSTRACT

A pressure sensitive removable adhesive is applied on ribbons used for wrapping the counted bundles of currency notes. The wrapping is in a way that a portion on the sides of the stack of notes will face enough amount of adhesive, to adhere each leave of the note with the ribbon strap, so that pulling out a note from a packed bundle will become difficult. Trie tape will have tear lines made of perforation or cuts so that it will disintegrate if opened. The adhesive can have chemical and/or colour coding for further security.

FIELD OF THE INVENTION

The invention generally relates to packaging sheet material andspecifically to packing currency notes in bundles e.g. 100s forfacilitating banking and other transactions involving bulk cash.

More specifically the proposed invention is to make a better, economicalremovable and tamper-resistant packing of banknotes non-invasively, yetretaining the ability to count those manually or mechanically byflipping, with the least change in the existing methods.

BACKGROUND OF THE INVENTION

Currency notes such as pounds, dollar bills or rupees are traditionallypacked in 100s with the help of staples and paper or plastic sheetribbons around an axis.

Staples have become out of fashion because of invasiveness anddifficulty in unpacking, including mutilation. Due to thesedisadvantages, now increasingly the currency note bundles are packedwith just a ribbon strap wrapped loosely around one of the axisgenerally vertical axis, traverse to the printed surface, so that thenotes could be still counted by flipping on a counting machine.

Depending only on ribbon strap around a pack of notes has led to adisadvantage because a note from a bundle can be easily removed now,without unpacking the bundle. This leads to further problems such as theneed to count the notes in the bundle each time it changes hand, and theresponsibility shifting immediately without recourse. Especially intransactions where bulk of cash handled e.g. in a treasury of a retailoperation, it has means that the good faith that each bundle has 100notes of a denomination is much lesser and the recourse in case of abundle has lesser than 100 notes is also lesser because it is easy toremove one from a pack. For example, in a bank teller counter, thecustomer has to completely depend on the teller and her countingmachine. Assuming an unavoidable error rate of counting machine, if thecustomer receives a note less in the pack, say 99 instead of 100, andshe leaves the counter without manually counting the notes, which may beimpractical in most situation, there is hardly any recourse. If thenotes were pilfer-packed e.g. stapled, the burden of proof would shifton the institution that put the staple, to establish whether there was acounting error or a note has been pilfered subsequently. Other knownalternative methods like shrink-wrap packing do not help because it goesto the other perceived extreme of complete dependence and accountabilityof the first packer, because these make subsequent counting withoutunpacking impossible.

In WO/2004/078485 SHEARLE has disclosed a clip for TAMPER EVIDENTDOCUMENT BUNDLE and has also cited some prior arts. The most importantdisadvantage in the SHEARLE is that it squarely depends on thecompressive pressure applied by a Clip, which will be more difficult andcostlier to apply and calibrate. There is a possibility of mutilating asheet if the pressure is too much. Moreover, the pressure appliedthrough the clip may not remain constant in time due to fatigue and dueto elasticity and plasticity in the material used for making the clip, acareful and persistent tampering attempt to loosen the grip gradually,e.g. by minutely shifting a number of sheets together or by inserting athin piece of metal dexterously between two portion in the stack, thebundle can be tampered with without leaving easily available evidence.Moreover, the Clip device is bulkier and will likely disturb theexisting arrangement of further packaging and processing of multiplestacks, e.g. requiring more space.

In the present invention the problem is solved by simplified means ofapplication of straps made of specialized glue tapes providing securingmeans and being quite different from the prior securing means ofcompressive clip and a tamper evident cover covering the clip, yetachieving better results of pilfer and tamper resistance, as explainedhereunder.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment the present invention contemplates using an adhesiveon a ribbon strap made of suitable sheet material, to be used for makingthe counted bundles of currency notes. Such ribbon strap tapes will havea rubber based or synthetic acrylic based removable adhesive, applied ina way that the portion of the tape falling on the two sides of the stackof notes will have an enough amount of adhesive, so that it will adhereeach leave of the note with the side of the tape, so that pulling out anote from a packed bundle will be difficult without opening the ribbon.The ribbon strap with adhesive will also exert a compressive pressure onthe sheets in the pack, making removal of a sheet without opening thepack more difficult.

Further, the strap will have partial cuts or perforations or weakenedtear lines so that it will disintegrate if opened or if a sheet ispulled from the stack. In a preferred embodiment, the adhesive will alsocomprise a colour so that if an attempt to pull a sheet is successfullymade, the coloured adhesive will leave a visible streak of smudge on theside of the pulled sheet and/or the remaining sheets in the bundle,making the tampering evident.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a conventional configuration of ribbon strap wrapper on astack of currency notes.

FIG. 2 shows an invented configuration in an embodiment.

FIG. 3 shows in more details some inventive features and embodiments.

FIG. 4 shows in an embodiment the colour mixed adhesive at the side of astack.

BRIEF DESCRIPTION WITH RESPECT TO DRAWINGS

A conventional prior art ribbon strap wrapper on a pack of currencynotes is shown in FIG. 1. It is in the shape of a tape, which is shownto have sides A, B, C, and E, at 120 and 130. Any one of the sidesoverlaps another e.g. E overlaps A, partly or fully and is fusedtogether by applying heat or is pasted together. The ribbon strap istightly wrapped around a vertical axis to keep the stack together, asshown at 110. Still it is possible to pull notes from the wrappedbundle.

In the invented ribbon strap wrapper comprises preferably a removableadhesive, which glues the sides B1 and D1 of the notes when the wrapperis placed on the stack, as shown in FIG. 2. At 210 is shown a ribbonstrap which can be preferably in the form of a removable pressuresensitive tape, which has a higher amount of such adhesive on portionsB1 and D1 which will bind the sides of the stack as shown at 250.

In the preferred embodiment, the adhesive on the portion of the strap incontact with the side of the stack of the sheets will be mixed with acolour to form a gel like substance to bind the substrate with thesheets. As shown in FIG. 4, the portion B of the stack in contact withthe strap has such a gel like coloured adhesive (410). The thickness ofthis adhesive is higher than the thickness of colourless adhesive in theother portions of the strap not in contact with the sides but is incontact with one of the faces of the sheets, as explained earlier. Thiswill leave some colour on the side of the notes but only in portion Busually (420) if the pack is opened conventionally i.e. by removing thestrap. However, if an attempt is made to pull a sheet or a number ofsheets from the stack as shown in 430, the rest of the portion A willalso come in contact with coloured adhesive at B and will leave a markAB on the side of the sheet (440). This will be useful in marking anddetection of a sheet pilfered from a pack, resulting in better securityof the pack.

The colour in the adhesive as mentioned above may be a visible colour ora colour invisible in normal conditions but visible in specialconditions e.g. in special lights or otherwise detectable throughspectrophotometric means. Such an adhesive with a special chemical or asabove can be specially formulated colour in a thixotropic gel form andapplied in a way that it releases colour due to pressure applied due topulling of the sheet. Such special formulation may contain colourencased in a pressure sensitive membrane or granules, which break downand release the said chemical on the colour on the sheet being pulledand or adjoining areas as explained above. For example, food gradeSilica Gel preferably in a thixotropic form can be suitably employed inthis embodiment. In another embodiment, Gel pen inks may be employed,which may be further modified in its formulation to achieve desiredproperties e.g. viscosity. For example, the adhesive may be in gel formsuch as those used in removable museum gel adhesives, with a chemicalidentifier, colour and other additives like water, polyvinyl alcohol,polyvinylpyrrolidone, polymers, defoamers etc. Such a gel can beformulated so as its viscosity breaks down under pressure.

However, in another embodiment it can be in the form of any othersubstrate such as in a conventional plastic band used to wrap a bundleof banknotes, on which an adhesive G is applied on sides B1 and D1 onlyand in that case the sides E1 and A1 can be fused or pasted togetherconventionally e.g. by application of heat. Alternatively, all sides canhave the pressure sensitive removable adhesive uniformly or there canhigher thickness of adhesive on side portions (B1, D1), than otherportions (A1, C1, E1). The ribbon strap also has preferably perforatedor weakened tear lines or die-punched partial cuts across each surfaceshown as dotted cross lines at 230, so that after being once used thetape will disintegrate when unwrapped or tampered with. Such lines canbe on a straight horizontal axis on the sides and on various angles onthe front and back, as shown. If an attempt to pull a note or a numberof notes is made without opening the strap, the strap will disintegrate.Alternatively the pilfered note as mentioned will get a streak of colouron its side extending right up to the top end of the sheet as shown inFIG. 4. If the colour is in a thixotropic gel form as explained earlier,it will form a smudge on the side glued to the strap and adjoiningareas.

A flap without any adhesive preferably in a colour different from therest of the substrate shown for example at E2 is provided for easypeeling off of the ribbon. The disclosed ribbon strap can be appliedeither along a vertical axis as shown at 210, or can be applied coveringa larger portion of the two sides and another side completely, as shownat 310 and 320. At 310 the ribbon strap is a wide ribbon strap e.g. 2inches wide, which fully covers a portion of the stack say e.g. onefifth, including the three sides. Alternatively, as shown in 320, anarrower ribbon strap e.g. 1 inch wide, is applied on the three sides,partly including two horizontal sides and one of the two vertical sidesfully, as shown. Once a bundle of notes is packed like this, its sidesin contact with the adhesive glues with the substrate and it becomesdifficult to pull a note or a few notes from the bundle without eitherdisintegrating the note or the ribbon. Yet the remaining portion of thebundle is free for being flipped for counting manually or on a countingmachine, as indicated at 320. The ribbon strap can have suitablemarkings and disintegrates on opening.

The application of the strap as disclosed here can be suitablyconfigured for a specific packaging line. For example, in a currencystrapping operation, a gripper and a bundler is generally utilized tomake packs of 100s. The strap conventionally used is either a plasticstrap two ends of which are fused together to form the wrapper or gluedtogether as in the case of a paper strap. In this case the bundler cancomprise a spool of adhesive tape, which is wrapped around a bundle andthen the bundle subjected to a pressure in case of a pressure sensitiveand heat in case of a heat sensitive adhesives. The pressure can beapplied either by an impact device or by application of a sustainedweight, or heat may be applied utilizing an electrical heating device.

The strength and specifications of the gum as well as the substrate withtear lines can be adjusted to impart the necessary adhesion to thebundle in a way that if one tries to pull a note or a few notes from thebundle it will not come out without breaking the note or the strap,because the adhesion strength combined with the compressive strength inforce will be more than the strength of either the sheet being pulled orthe weakened strap. For example if a number of notes are pulled, theribbon strap will break because of the said tear lines.

In another example embodiment, the individual sheets may additionallyhave a narrow band of repositionable adhesive on one of its sides likein Post-it® pads of 3M®, making it impossible to pull a sheet withoutbreaking the ribbon as explained.

When the ribbon strap is peeled off, most or all of the removableadhesive will come out with it, though likely leaving some trace behind.The remaining adhesion between , the individual leaves of notes due tosuch trace if any will be so low as to not cause any problem inunbundling the notes, also because when the notes from a pack from whichribbon strap has been removed will be likely pulled on a vertical axisto the adhered surface. Therefore the individual leaves of notes willcome out easily.

The property of a removable adhesive to leave residual traces as abovecan be also effectively utilized by adding an invisible and difficult todecipher chemical in the adhesive which can be deciphered later as anadditional information for detecting counterfeit. In addition, forexample, a special dye such as a fluorescent dye, which glows in aparticular light or another chemical with a distinct marker may beutilized. Further, various chemicals may be used in different series anda log kept for cross-checking later the integrity of a particular notewith a particular number supposed to have a chemical residue due to theadhesive band, as per the log.

In another embodiment, a heat sensitive removable adhesive can be used.In this case an applicator module will apply heat to make the adhesiveglue the sides of the notes with the ribbon, as explained. In analternative embodiment, a permanent adhesive or a repositionablepermanent adhesive may be applied instead of a removable adhesive. Suchadhesive form adhesion permanently so that the substrate cannot beremoved after a specified passage of time, without destruction. In thisembodiment, the permanent adhesive is utilized only on a portion whichbinds with a side of a stack and not on the rest of the portion viz.that which is in touch with a front or back of the notes, which can havea removable adhesive or may not have any adhesive and is fused togetherconventionally e.g. by heat application on plastic substrate. Despitethe permanent adhesion of a small portion of a side of a note to thesubstrate of the strap, it will be possible to take out the notes oncethe strap is opened by pulling individual notes vertically from the bedof the stack, as is done in case of loosely bound notepad stacks. In yetanother embodiment the adhesive used to adhere the sheets together is apermanent adhesive such as those used in binding a note-pad stacks e.g.in office letter-pad, and a ribbon strap or tape with aremovable-adhesive is pasted on top is the permanent adhesive liningfusing the edges of the sheets together. As a result, it will beimpossible to pilfer a note from the bundle, and a leaf from the bundlecould be taken out only after the strap with removable adhesive has beenremoved and then the leaves are pulled in a vertical direction to thepad, as is done in case of pulling an office letter-head from its pad.

As only a very small adhesion surface can be contemplated on the sidesof the stack in contact with the adhesive, the tack, peel-strength, thestorage modulus (G′) of the adhesive will be suitably calibrated to havethe desired level of integrity required. In the best embodiment asynthetic acrylic removable adhesive of low peel strength and high tackand thus a low G′, such as those used in 3M® products is applied in asuitable thickness which will be generally higher than the thickness ofglue in the conventional tapes made of such adhesives, e.g. 250 microns.Such adhesive usually contain a plasticiser and a tackifier amongstother constituents. For example, a mixture of water, acrylic polymer,stearic acid, sodium salt, polyethylene glycol, N-VINYLPYRROLIDINONEPOLYMER, propanol, ether etc. used in making removable glue stick of 3M®may be utilized as the adhesive for this purpose. Likewise a suitablesubstrate such as a paper, vinyl or non-woven fabric tape can be usedfor making the ribbon strap with adhesives as above.

Various base polymers can be used in a removable pressure sensitiveadhesive formulation since the rheological properties are significantlydetermined by the formulation (base polymer, plasticiser, tackifier andother additives) rather than the base polymers alone. Acrylic(water-based and solvent-based), natural rubber, and styrene blockcopolymers are the most popular base polymers in these formulations.Solvent and water based removable pressure sensitive adhesives areavailable from many suppliers including Avery Dennison®, Ichemco®, 3M®,and Mactac®.

The ribbon strap apart from being wrapped around a conventional verticalaxis as shown in 110 and 240 can also be applied around the edges up tosay for example one-fifth of its horizontal surface, as shown in 310 and320, to impart additional pilfer-resistant integrity and yet letting thepack remain countable by flipping the individual notes by a conventionalcounting machine as shown at 330.

A special pressurizing device can be utilized to keep the strapped packsunder vertical pressure to form the adhesion along the sides of the packproperly. This pressure device may apply a high impact for a short timeor a moderate impact for a long time. The tightness with which theribbon strap is wrapped around the bundle will also provide a pressureon the adhesive. Such tightness is calibrated at a level to apply apressure yet not break down on the tear lines provided unless apilferage attempt viz. to take out a note is made. This feature achievesthree objectives (a) providing a pressure on the pressure sensitiveadhesive for gluing; (b) providing compressive pressure on the stack;and (c) to provide a decompressive pressure on the strap to weaken itsstrength on the tear lines, increasing the possibility of itsdisintegration if an attempt for pilferage or tampering is made. Thesaid tightness will depend on the type of the substrate of the ribbon,the adhesive and the type of the weakening e.g. perforation or cut.

The above method and devices can be most effectively utilized in bankingoperations especially in central bank treasuries where the notes arefirst printed. The disclosed invention can be suitably packaged as apart of currency printing machinery. Rolls of ribbons with adhesiveportions as disclosed above can be applied after the notes have beenprinted and stacked in bundles e.g. of 100s. The ribbon strap can beapplied through an automatic packaging machine. A pressure is applied onthe ribbon strap to make the adhesive stick. The pressure can be appliedby a short impact of high force or a long impact of moderate force e.g.keeping the adhered side portions of the packed notes under a weight of1 kilogram per square centimeter for 10 seconds. To check thereliability of the pilfer-resistant property of the packs made as perthe disclosures, a statistical quality control method can be appliedwhereby packs can be randomly selected and a note randomly selected formthe said pack can be pulled applying a force, to measure shift fromadhesion if any and take remedial measure as per a table. This aspect ofthe process can be suitably automated. For example, an alarm feature cantrigger a supervisor to stop the packing line for taking correctivemeasures e.g. changing a ribbon strap spool, if a shift is determinedbeyond a specified tolerance.

The disclosures can also be applied to a modern currency countingmachine, to include a wrapping device accordingly. With suitableadaptations, the disclosures can be applied in many Other packagingapplications e.g. for bundling expensive cut sheets.

One of the technical problems the above invention solves is how tonon-invasively make pilfer and tamper proof pack of sheet material sothat it could still be counted by flipping without breaking the package.As disclosed above, use of adhesive will result in pilfer-resistant anduse of weakened tear lines in tamper-resistant qualities. These apartform increasing reliability and accountability will also decrease thechances of unintended shifting of the sheets in a strapped pack, e.g.while transporting. It provides an effective substitute for stapling,avoiding its invasiveness. The disclosed device will work well withother security systems such as those that involve release of ink bypyrotechnic charge in a box of notes, on certain parameters beingbreached.

Thus it is evident that disclosed herein is a pilfer and tamperresistant ribbon strap for packaging sheet material including currencynotes comprising a removable ribbon strap (210, 220, 230) for wrappingbundles or stacks such as 100s of sheet material such as currency notes,the said strap having on at least a portion (B1, D1) of its surface anadhesive such as a pressure sensitive removable adhesive to bind atleast one of the sides of the leaves (250) in the said bundle or stackto secure the said sheets from being pilfered or tampered. The saidribbon strap also comprises a perforated or weakened or punched tearlines on at least one of the said portion of the said strap, the saidstrap being disintegratable along at least one of the said lines, on atleast one of the said sheets being pulled or removed from the saidbundle or stack, or the strap being removed from the said bundle orstack. The said adhesive in the said strap can comprise invisiblechemical markers identifiable by chemical analysis, for markingauthenticity of the sheets, a colour visible under normal or specifiedconditions. The said adhesive, chemical or colour can be in a gel form,in particular a thixotropic gel form such as a silica thixotrope. Suchgel can comprise polymers such as polyvinyl alcohol andpolyvinylpyrrolidone, and additives such as water, defoamers,plasticizer and presevative; formulated so as its viscosity breakingdown due to pressure applied on pilfering the bundle or stack. There cana higher thickness of an adhesive on a portion (B1, D1) of said strapthan another portion (A1, C1, E1) of the said strap, the said higherthickness of said adhesive being capable of adhering the said at leastone of the sides of the leaves (250) of the said stack or bundle ofsheets. The ribbon strap can be the form of a continuous roll of anadhesive tape, applicable on a bundle or stack of sheets.

Disclosed further is a method of forming a pilfer and tamper resistantpacking of a bundle or stack such as in 100s of a sheet material likecurrency notes comprising; wrapping the ribbon strap (210, 220, 230)around at least one axis of the bundle or the stack to adhere at leastpartially a portion of at least one of the sides (250) of each of thesaid stack, with a corresponding adhesive portion of the said ribbon,said adhesion being secured on applying a pressure or heat on the saidadhesive portion in contact with the said side of the stack, theremaining portion remaining free for being counted by flipping the saidnotes in the said bundle. The above method can further comprise steps ofdetermining integrity of the said pilfer resistant pack by randomlyselecting a sheet from a pack, applying a measured pulling force on thesaid note, measuring shift of the said note and determining a value ofintegrity of the said pack in relation to the degree of the shift of thesaid sheet. Also disclosed is apparatus for pilfer and resistantpackaging of sheets as above, comprising a gripping device, a bundlingdevice, a measuring device, a wrapping device, a cutting device, apressure or a heating device, a sensor device and an alarm device.Further an apparatus for testing the integrity of the pilfer and tamperresistant packs according to claim 8 comprising; a random sample pickingdevice, a pulling device, a measuring device to measure the shift, acalculation device to arrive at an integrity score and an alarm deviceto signal a negative score if any is disclosed. These apparatus can be apart of a printing and packing assembly wherein the packaging apparatusis integrated with a printing line of sheets such as currency notes.

The present invention as herein narrated above and illustrated shouldnot be read and construed in a restrictive manner as variousadaptations, changes and modifications are possible within the scope andlimit of the invention as defined and encompassed in the appendedclaims.

1. A pilfer and tamper resistant ribbon strap for packaging sheetmaterial including currency notes com_(p)rising of: a removable ribbonstrap (210, 220, 230) for wrapping bundles or stacks such as 100s ofsheet material such as currency notes, the said strap having on at leasta portion (B1, D1) of its surface an adhesive such as a pressuresensitive removable adhesive to bind at least one of the sides of theleaves (250) in the said bundle or stack to secure the said sheets frombeing pilfered or tampered; a perforated or weakened or punched tearlines on at least one of the said portion of the said strap, the saidstrap being disintegratable along at least one of the said lines, on atleast one of the said sheets being pulled or removed from the saidbundle or stack, or the strap being removed from the said bundle orstack.
 2. The ribbon strap according to claim 1, the said adhesivecomprising an invisible chemical marker identifiable by chemicalanalysis, for marking authenticity of the sheets.
 3. The ribbon strapaccording to claim 1, the said adhesive comprising a colour visibleunder normal or specified conditions.
 4. The ribbon strap according toclaim 1 to 3, the said adhesive, chemical or colour being in a gel form,in particular a thixotropic gel form such as a silica thixotrope.
 5. Theribbon strap according to claim 4, the said gel comprising polymers suchas polyvinyl alcohol and polyvinylpyrrolidone, and additives such aswater, defoamers, plasticizer and presevative; the said gel formulatedso as its viscosity breaking down due to pressure applied on pilferingthe said bundle or stack.
 6. The ribbon strap of the preceding claimscomprising a higher thickness of an adhesive on a portion (B1, D1) ofsaid strap than another portion of the said strap (A1, C1, E1), the saidhigher thickness of said adhesive being capable of adhering the said atleast one of the sides of the leaves (250) of the said stack or bundleof sheets.
 7. The ribbon strap according to the preceding claims,wherein the said ribbon strap is in the form of a continuous roll of anadhesive tape, applicable on a bundle or stack of sheets.
 8. A method offorming a pilfer and tamper resistant packing of a bundle or stack suchas in 100s of a sheet material like currency notes comprising; wrappingthe ribbon strap (210, 220, 230) around at least one axis of the bundleor the stack to adhere at least partially a portion of at least one ofthe sides (250) of each of the said stack, with a corresponding adhesiveportion of the said ribbon, said adhesion being secured on applying apressure or heat on the said adhesive portion in contact with the saidside of the stack, the remaining portion remaining free for beingcounted by flipping the said notes in the said bundle.
 9. The method ofclaim 7 further comprising determining integrity of the said pilferresistant pack by randomly selecting a sheet from a pack, applying ameasured pulling force on the said note, measuring shift of the saidnote and determining a value of integrity of the said pack in relationto the degree of the shift of the said sheet.
 10. An apparatus forpilfer and resistant packaging of sheets as per claims 7 comprising agripping device, a bundling device, a measuring device, a wrappingdevice, a cutting device, a pressure or a heating device, a sensordevice and an alarm device.
 11. An apparatus for testing the integrityof the pilfer and tamper resistant packs according to claim 8comprising; a random sample picking device, a pulling device, ameasuring device to measure the shift, a calculation device to arrive atan integrity score and an alarm device to signal a negative score ifany.
 12. The apparatus of claims 9 and 10, as a part of an automatedprinting and packing assembly wherein the said packaging and testingapparatus is integrated with a printing and packing line of sheets suchas currency notes.